Just add the Epsom Salt after each water change, that way it doesn't matter. Epsom is really effective against constipation/bloat, the most common cause of SBD, so don't stress. Epsom is extremely safe stuff. It won't mess anything up.

Is the Epsom salt ok to use in a live planted tank? My Betta has been acting a bit out of character lately.(a bit lethargic and darting around his tank at random times- he even swam into his rocks at the bottom once and darted back up:/) He pooped today and the end of the poo was white, which makes me think parasites. If I treat his 5 gallon tank with epsom salt, will it hurt the plants? Would it be better to quarantine him? He has not gotten to the point where he looks sick, but I just had a betta die from internal parasites(I think, and maybe sbd), so, I dont want to wait and take any chances with him.

I have him in a 5 gallon, heated and filtered tank. Any thoughts on the best, least stressful way to treat at this stage. I really just want to take preventative measures. I treat my water with Seachem Prime and use Stress Coat occasionally. I assume, when using the EP salt I would do a daily water change and then replenish? Also, if I put the salt directly in his tank, should I acclimate him over a half hour/hour with it?

Also, I was going to start soaking his pellets in Garlic to help with possible parasites.

Epsom salt does help with bloating and SBD. Do not use it for more than 2 weeks at a time beyond that will cause damage to your betta.
Also try fasting him for 2-3 days to give him a change to clean his system out.

BrookeGrace - I recommend switching his food to either New Life Spectrum Betta pellets or Omega One Betta Buffet.

Foods that contain a lot of grains/fillers can cause constipation, bloating and/or buoyancy issues. Look at the label of your current pellets, and look for words like "gluten, corn, soybean, potato, wheat, rice, etc." If you see words like this, consider switching to a high-protein pellets such as New Life Spectrum or Omega One. These two brands are well-tolerated by Bettas, and cause fewer digestive issues.

LionelFishy - Yes, Epsom salt can be used in a tank that has live plants. In fact, Epsom salt is often used as fertilizer! (However, don't use Aquarium salt in a planted tank.)

White feces can be caused by several things, including parasites and stress. I recommend that you start a new thread about your fish. This will allow people to look at him, and read about his symptoms. Be sure to include the information on the sticky located here.

VivianKJean - Hm, no. It can be OK to use Epsom salt for a longer period of time. It simply depends on what condition is being treated. I think you may be thinking of Aquarium salt. Aquarium salt has a high sodium content. This places stress on the kidneys, and can lead to fluid retention or bloating, etc. I do agree with your comment about fasting a bloated fish for several days prior to medicating it. Often, fasting alone can help resolve the bloating/fluid retention. If it doesn't, the next step is often either Epsom salt (magnesium sulfate heptahydrate), or frozen/live daphnia. Both Epsom salt and frozen/live daphnia have laxative effects, which can help 'clean out' a constipated fish. (Don't feed freeze-dried foods though, as these can cause additional constipation issues.)